The present invention relates to a fastener device for holding papers or the like on a leaf of a file folder or the like.
By way of background, there are a number of fastener devices known in the art which include an overlay member which secures a prong member to a file folder. Devices of this type are shown in U.S. Pat. Nos. 3,271,829, 3,641,632, 3,741,385 and 3,867,743. Devices of this type required an overlay member to be secured to the leaf of a file folder or the like by hot melt adhesive which was unusually strong. This prevented the fastener devices from being mounted on file folders by individuals who did not have the proper equipment to activate the hot melt adhesive. Attempts were made to affix fastener devices directly to file folders by means of pressure-sensitive adhesive. However, these attempts were not commercially acceptable because of the fact that the adhesive was applied directly to the central portion of the prong member or to a two-sided tape with no cushioning qualities and it tended to pull away from the file folder either because of the shock to which it was subjected in use and/or because of the "memory" of the prong member, when curved, which exerted a continual force on the adhesive until the bond was broken. It is with overcoming the foregoing deficiencies of the prior art that the present invention is concerned.